Photoexcited Carrier Dynamics Of Low Dimensional Materials And Cellular Therapy

2022-09-14 Dr. Srabani Kar, Postdoctoral researcher, Engineering Design, IIT Madras.

ABSTRACT :

I shall present the photoexcited hot carrier dynamics of low (1D and 2D) dimensional nanomaterials using time-resolved terahertz spectroscopy. Time-resolved terahertz (THz) spectroscopy offers non-contact measurement of conductivity in unexcited and photoexcited states of materials along with the carrier relaxation dynamics. I shall discuss the unique negative and positive photoconductivity responses of single-layer graphene (SLG), and bilayer gr aphene (BLG) in the 0.5-2.5 THz after photo excitation with 800 nm 50 fs optical pump pulse. These dynamical responses were understood by applying semi-classical Boltzmann transport theory for the hot carriers. Next, I shall briefly present the studies on photoexcited semiconducting nanowires showing plasmonic responses in the terahertz range. The detailed investigations of the plasmon dynamics provide non-contact measurement of intrinsic mobilities and surface recombination rates of these nanowires, which are essential for any optoelectronic device applications. Finally, I shall briefly present how the ultrafast hot carrier dynamics of nanostructures and nanomaterials can be extensively applied for intracellular research in the field of biomedical research.

Event Name

Seminars

Place

S N Bose Hall (HSB 210)

Start Time

15:00

End Time

16:00

External Link

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